Chapters 4 & 5 Test

Vocabulary

Activation energy

Minimum amount of energy required to activate reactants and trigger a chemical reaction

Active site

Region of an enzyme into which a particular substrate fits

Amino acid

Monomer that makes up proteins; Contains carboxyl and amino functional groups, hydrogen, plus a unique side group

Atom

Smallest particle of an element

Atomic number

Number of protons in an atoms nucleus that is unique to each element

Carbohydrate

Organic compound made of sugar molecules

Catalyst

Compounds that speeds up chemical reactions

Cellulose

Polysaccharide consisting of glucose monomers that reinforces plant cell walls

Chemical reaction

Breaking of old and formation of new chemical bonds that result in new substances

Cholesterol

Steroid molecule present in the plasma membranes of animal cells

Compound

Substance containing two or more elements chemically combined in a fixed ratio

Covalent bond

Chemical bond that forms when two atoms share electrons

Dehydration reaction

Process of building a polymer chain; The removal of water that occurs when a monomer is added to the chain

Denaturation

Loss of normal shape of a protein due to heat or other factor

Disaccharide

Sugar made from two monosaccharides

Electron

Subatomic particle with a single unit of negative electric charge

Element

Pure substance that cannot be broken down into other substances by chemical or physical means

Enzyme

Specialized protein that catalyzes the chemical reactions of a cell

Fat

Organic compound consisting of a three-carbon backbone (glycerol) attached to three fatty acids

Functional group

Group of atoms within a molecule that interacts in predictable ways with other molecules

Glycogen

Polysaccharide in animal cells that consists of many glucose monomers

Hydrocarbon

Organic molecule composed of only carbon & hydrogen atoms

Hydrolysis reaction

Process of breaking down a polymer chain; The use of water to break apart polymer chain

Hydrophilic

Attracts water molecules

Hydrophobic

Avoids water molecules

Inorganic molecule

Non-carbon-based molecule

Ion

Atom that has become electrically charged as a result of gaining or losing an electron

Ionic bond

Chemical bond that occurs when an atom transfers an electron to another atom

Lipid

One of a class of water-avoiding compounds

Matter

Anything that occupies space and has mass

Molecule

Two or more atoms held together by covalent bonds

Monomer

Small molecular units that is the building block of a larger molecule

Monosaccharide

Sugar containing one sugar unit

Neutron

Subatomic particle that has no charge is electrically neutral

Nucleus

In an atom, the central core that contains protons and neutrons

Organic molecule

Carbon-based molecule

Polymer

Long chain of small molecular units (monomers)

Polypeptide

Chain of linked amino acids

Polysaccharide

Long polymer chain made up of simple sugar monomers

Product

Material created as a result of a chemical reaction

Protein

Polymer constructed from a set of 20 amino acid monomers

Proton

Subatomic particle with a single unit of positive electric charge

Reactant

Starting material for a chemical reaction

Saturated fat

Fat in which all three fatty acid chains contain the maximum possible number of hydrogen atoms; All C atoms in fatty acid form single bonds with each other & rest of bonds with hydrogen atoms

Starch

Polysaccharide in plant cells that consists entirely of glucose monomers

Steroid

Lipid molecule with four fused carbon rings

Substrate

Specific reactant acted on by an enzyme

Trace element

Element critical to health that makes up less than 0.01 percent of body mass

Unsaturated fat

Fat with less than the maximum number of hydrogens in one or more of its fatty acid chains; Some C atoms are double-bonded to each other

Concepts to Know

Name FOUR elements that make up 96% of living matter.

Oxygen (O), Carbon (C), Hydrogen (H), Nitrogen (N)

Name FOUR elements that make up the remaining 4% of living matter.

Calcium (Ca), Phosphorus (P), Potassium (K), Sulfur (S)

Name TWO trace elements & their purposes

Iodine

You need 0.15 mg / day. If you dont get it, your thyroid gland wont function properly.

Iron

Essential for carrying oxygen in your blood

How are elements & compounds different?

Elements are substances that cannot be broken down into any other substances by chemical means, while compounds are substances made from the chemical combination of two or more elements in a fixed ratio.

Give TWO examples of how a compounds properties differ greatly from those of its component elements

H2, Hydrogen gas + O2, Oxygen gas Water, H2O is a liquid

Na, silvery-gray Sodium metal + Cl, yellowish green Chlorine gas NaCl, White table salt crystals

Describe the structure of an atom Tell the name, charge & location of all subatomic particles

Protons, p+ & Neutrons, no are located in the nucleus

Electrons, e- are constantly moving outside the nucleus

Describe the significance of the number of electrons in an atoms highest energy level.

The number of electrons in an atoms highest energy level determines how the atom reacts. Atoms will react when the highest energy level is partly filled.

Describe how an ionic bond forms & draw an example.

An ionic bond forms when oppositely charged ions formed from the transfer of electrons are attracted to one another

Describe how a covalent bond forms & draw an example.

In a covalent bond, electrons are shared between atoms.

Name THREE ways a molecule can be represented & give an example.

Chemical Formula

Structural Formula

Space-Filling Model

H2O

O

/ \

H H

Identify & Draw FOUR Functional Groups

Hydroxyl

Carbonyl

Carboxyl

Amino

H H

| |

H C C OH

| |

H H

H O H

| || |

H C C C H

| |

H H

OH \\| C C H

/ | HO H

H H

\ |

N C H

/ |

H H

Draw Building a Polymer Chain

Draw Breaking a Polymer Chain

Sugars Elemental Components & Ratio

1 carbon : 2 hydrogen : 1 oxygen

PRIMARY FUNCTIONS OF CARBOHYDRATES

Main fuel supply for cellular work; Use carbon skeletons of monosaccharides as raw material for manufacturing other kinds of organic molecules (larger carbs or fats);

Examples of Monosaccharides

Glucose (in both straight-chain and ring-shaped forms), fructose, galactose

Name THREE polysaccharides, describe their functions & where they are found

Starch

Glycogen

Cellulose

Starch chains serve as sugar stockpiles; Broken down for stored glucose to become availablePotatoes, rice, corn

More highly branched than starch; Stored as granules in liver/muscle cells; Body breaks down glycogen granules to release glucose for energy

Serve as building materials protect cells, stiffen plant; Multiple cellulose chains linked together with hydrogen bonds, forming cable-like fibers

Why cant humans digest cellulose?

They lack the molecule necessary to break the bonds between the glucose monomers in cellulose

Is cellulose nutritious? What is its purpose?

Fiber passes unchanged through your digestive system. It helps keep the digestive system healthy, but doesnt serve as a nutrient.

Are carbohydrates hydrophilic? Why? Name one way this is helpful and one way this is not ideal.

Carbohydrates are hydrophilic. Due to many hydroxyl groups in sugar units.

Mono-/Di-saccharides dissolve readily in water to make sugary solutions.

Polysaccharides (like cellulose) are too large to dissolve. This prevents cotton clothing from dissolving in water, but allows cotton bath towels to absorb water

PRIMARY FUNCTION OF LIPIDS

Lipids acts as a boundary that surrounds & contains the aqueous contents of body cells; Circulate as chemical signals to cells; Store energy in your body

Know the structure of fats.

Glycerol (3-C backbone) attached to 3 fatty acids (which contain long hydrocarbon chains)

Know the function of fats.

Store energy for later use; Fatty tissues cushion organs; Provide body with insulation

Examples of saturated fats

Solid at room temperature; Animal fats such as lard & butter

Examples of unsaturated fats

Fats in fruits, vegetables & fish; Corn, olive, & other vegetable oils

Diets high in saturated fats cause

The build-up of lipid-containing deposits, called plaques, within the walls of blood vessels. Plaques can reduce blood flow & contribute